Typically, the manufacture of high-quality electrical contacts has involved the use of gold whose properties of low contact resistance and high chemical stability are key advantages in such usage. However, as the price of gold remains high, efforts continue at finding alternative materials for contact manufacture.
Prominent among such alternatives are precious metals other than gold; e.g., silver-palladium alloys have been found suitable for certain applications. While such alternate alloys are less expensive than gold, still further cost reduction is desired, and nonprecious metal alloys such as, e.g., copper-nickel alloys have also been investigated for contact resistance and stability over time. See S. M. Garte et al., "Contact Properties of Nickel-Containing Alloys", Electrical Contacts, 1972, Illinois Institute of Technology.